ABI (Ankle-Brachial Index)

What is an ABI and what does it do?

The ankle-brachial index (ABI) is a measurement that is useful to your physician in evaluating the adequacy of the circulation in your legs. It can also be used to follow the improvement or worsening of leg circulation over time. To obtain the ABI, your physician measures your blood pressure in your ankle and in your arm. Your physician will compare the two numbers by forming a ratio to determine your ABI.

Normally, the blood pressures in your ankle and arm should be about equal. But if your ankle pressures are lower than your arm pressures, your leg arteries are probably narrowed.

Who performs the test?

The test is performed by a licensed Respiratory Therapist.

Where does it take place?

At Jackson Hospital in the Respiratory Department.

How long does it take?

About 30–45 minutes.

What can I do to make it a success?

Please be sure to bring your doctor’s orders with you the day of your test. Allow 15 minutes to register.

Wear comfortable clothing and shoes that can be removed easily (we must be able to place blood pressure cuffs on your arms and legs).

Please do not use lotions or oils on the legs and arms prior to the test.

What should I do before the exam?

There are no special dietary restrictions for this study.

You should take any medications as you normally would.

What happens during the exam?

You will be asked to remove your pants, socks and shoes and put on a hospital gown.

You will be lying flat during the test. The technologist will place pressurized cuffs (similar to blood pressure cuffs) on your legs and arms.

What should I do after the exam?

You may resume normal activity after your study. Your test will be reviewed and interpreted by a physician. Your physician should have the results of your study in 24-48 hours.